David Wechsler

1896-1981
American experimental and clinical psychologist who developed new types of intelligence tests.

David Wechsler developed the first standardized adult intelligence test, the Bellevue-Wechsler Scale, in 1939. Likewise, the Wechsler Intelligence Scale for Children, published in 1949 and revised in 1974, was considered to be the best test available. The concept that intelligence involves the abilities necessary to succeed in life was one of Wechsler's major contributions to psychology. He promoted the idea that intelligence includes personality traits and emotional states, as well as mental abilities, and that all of these should be measured to assess intelligent behavior in one's environment. Wechsler also promoted the idea that educational, cultural, and socioeconomic factors must be considered when evaluating intelligence. The author of more than 60 books and articles, Wechsler served as president of the American Psychopathology Association in 1959-60 and earned the Distinguished Professional Contribution Award of the American Psychological Association in 1973.

Born in Lespedi, Romania, in 1896, Wechsler was the youngest of seven children of Moses S. Wechsler, a Hebrew scholar, and Leah W. Pascal, a shopkeeper. The family moved to New York City in 1902, and Wechsler graduated from the City College of New York in 1916. He earned his master's degree in experimental psychopathology the following year, working with Robert S. Woodworth at Columbia University. His dissertation was published in 1917.

Recognizes the limitations of intelligence testing

During the First World War, Wechsler worked at Camp Yaphank on Long Island under E. G. Boring, scoring intelligence tests for the army as a civilian volunteer. He continued working with intelligence testing while serving with the army's Psychological Division of the Sanitary Corps at Fort Logan, Texas. These experiences convinced Wechsler of the limitations of available intelligence tests, particular for uneducated or foreign-born adults. After serving in France, Wechsler became an army student at the University of London in 1919, where he studied with Karl Pearson and Charles Spearman, who shared his interests in intelligence testing. Wechsler then obtained a two-year fellowship to study in Paris with the physiologist Louis Lapique and the experimental psychologist Henri Piéron. Wechsler's research focused on the psychogalvanic response, the changes in electrical conductivity of the skin that accompany emotional changes.

After spending the summer of 1922 working at the Psychopathic Hospital in Boston, Wechsler returned to New York City, as a psychologist with the Bureau of Child Guidance. There, for the next two years, he administered psychological tests. Concurrently, he completed his Ph.D. dissertation at Columbia under Woodworth. This work, "The Measurement of Emotional Reactions: Researches on the Psychogalvanic Reflex," was published in Archives of Psychology in 1925.

During the next seven years, Wechsler had a private clinical practice, as well as working as acting secretary of the Psychological Corporation, which later published his intelligence tests. He also was a psychologist at the Brooklyn Jewish Social Service Bureau. Wechsler continued to look for more broadly based measurements of intelligence. His 1930 article in The Scientific Monthly was expanded into his 1935 book, The Range of Human Capacities. In this work, Wechsler argued that psychologists had overestimated the range of variations among individuals and that human beings were actually surprisingly similar. He further argued that abilities peaked at a certain age and then began to decline. Wechsler began devising a variety of different types of tests. In 1926, he developed "Tests for Taxi Cab Drivers" for the Yellow Cab Company of Pittsburgh.

Develops new ways to measure intelligence

In 1932, Wechsler began his long career as chief psychologist at the Bellevue Psychiatric Hospital in New York and, the following year, joined the faculty of the New York University College of Medicine. Although he engaged in a variety of research projects, his major focus continued to be intelligence. At Bellevue, Wechsler tested both children and adults from a wide variety of backgrounds and with numerous problems. Again, he found that traditional testing methods were not suitable. In particular, he concluded that the commonly used Binet tests of intelligence were too narrow in scope and were inappropriate for adults. In addition to his well-known tests for adults and children, Wechsler developed the Army Wechsler (1942), the Wechsler Adult Intelligence Scale in 1955 which he revised in 1981, and the Wechsler Preschool and Primary Scale of Intelligence in 1967. Wechsler's tests measured abilities in performing tasks as well as mental abilities. He also introduced the deviation quotient, a new calculation that compared individuals with their peer group, rather than calculating a "mental age" as in the Binet tests. The deviation quotient corrected for abilities that changed with age and made it easier to detect abnormalities. In 1939, Wechsler published The Measurement of Adult Intelligence.

Wechsler never lost sight of the limitations of his intelligence tests. Although his tests often are interpreted as a clear measure of intelligence, Wechsler himself believed that they were useful only in conjunction with other clinical measurements. To Wechsler, assessments were far superior to mere testing.

Wechsler's first wife, Florence Felske, died in an automobile accident three weeks after their marriage in 1934. In 1939, he married Ruth A. Halpern and the couple had two children. During World War II, Wechsler acted as special consultant to the secretary of war and, beginning in 1948, he was consultant to the Veterans Administration. In 1947, Wechsler participated in a mission to Cyprus to form a mental health program for Holocaust survivors. A founder of Hebrew University in Jerusalem, he was Beber Visiting Professor of Clinical Psychology there in 1967, the year he retired from his posts at Bellevue and New York University. Wechsler was the recipient of numerous awards, including a special award from the American Association on Mental Deficiency and an honorary doctorate from Hebrew University. Wechsler died in New York City in 1981.